Source code for evennia.help.utils

"""
Resources for indexing help entries and for splitting help entries into
sub-categories.

This is used primarily by the default `help` command.

"""

import re

from django.conf import settings

# these are words that Lunr normally ignores but which we want to find
# since we use them (e.g. as command names).
# Lunr's default ignore-word list is found here:
# https://github.com/yeraydiazdiaz/lunr.py/blob/master/lunr/stop_word_filter.py
_LUNR_STOP_WORD_FILTER_EXCEPTIONS = [
    "about",
    "might",
    "get",
    "who",
    "say",
    "where",
] + settings.LUNR_STOP_WORD_FILTER_EXCEPTIONS


_LUNR = None
_LUNR_EXCEPTION = None

_LUNR_GET_BUILDER = None
_LUNR_BUILDER_PIPELINE = None

_RE_HELP_SUBTOPICS_START = re.compile(r"^\s*?#\s*?subtopics\s*?$", re.I + re.M)
_RE_HELP_SUBTOPIC_SPLIT = re.compile(r"^\s*?(\#{2,6}\s*?\w+?[a-z0-9 \-\?!,\.]*?)$", re.M + re.I)
_RE_HELP_SUBTOPIC_PARSE = re.compile(r"^(?P<nesting>\#{2,6})\s*?(?P<name>.*?)$", re.I + re.M)

MAX_SUBTOPIC_NESTING = 5


[docs]def help_search_with_index(query, candidate_entries, suggestion_maxnum=5, fields=None): """ Lunr-powered fast index search and suggestion wrapper. See https://lunrjs.com/. Args: query (str): The query to search for. candidate_entries (list): This is the body of possible entities to search. Each must have a property `.search_index_entry` that returns a dict with all keys in the `fields` arg. suggestion_maxnum (int): How many matches to allow at most in a multi-match. fields (list, optional): A list of Lunr field mappings ``{"field_name": str, "boost": int}``. See the Lunr documentation for more details. The field name must exist in the dicts returned by `.search_index_entry` of the candidates. If not given, a default setup is used, prefering keys > aliases > category > tags. Returns: tuple: A tuple (matches, suggestions), each a list, where the `suggestion_maxnum` limits how many suggestions are included. """ global _LUNR, _LUNR_EXCEPTION, _LUNR_BUILDER_PIPELINE, _LUNR_GET_BUILDER if not _LUNR: # we have to delay-load lunr because it messes with logging if it's imported # before twisted's logging has been set up from lunr import get_default_builder as _LUNR_GET_BUILDER from lunr import lunr as _LUNR from lunr import stop_word_filter from lunr.exceptions import QueryParseError as _LUNR_EXCEPTION from lunr.stemmer import stemmer # from lunr.trimmer import trimmer # pre-create a lunr index-builder pipeline where we've removed some of # the stop-words from the default in lunr. stop_words = stop_word_filter.WORDS for ignore_word in _LUNR_STOP_WORD_FILTER_EXCEPTIONS: try: stop_words.remove(ignore_word) except ValueError: pass custom_stop_words_filter = stop_word_filter.generate_stop_word_filter(stop_words) # _LUNR_BUILDER_PIPELINE = (trimmer, custom_stop_words_filter, stemmer) _LUNR_BUILDER_PIPELINE = (custom_stop_words_filter, stemmer) indx = [cnd.search_index_entry for cnd in candidate_entries] mapping = {indx[ix]["key"]: cand for ix, cand in enumerate(candidate_entries)} if not fields: fields = [ {"field_name": "key", "boost": 10}, {"field_name": "aliases", "boost": 7}, {"field_name": "category", "boost": 6}, {"field_name": "tags", "boost": 5}, ] # build the search index builder = _LUNR_GET_BUILDER() builder.pipeline.reset() builder.pipeline.add(*_LUNR_BUILDER_PIPELINE) search_index = _LUNR(ref="key", fields=fields, documents=indx, builder=builder) try: matches = search_index.search(query)[:suggestion_maxnum] except _LUNR_EXCEPTION: # this is a user-input problem matches = [] # matches (objs), suggestions (strs) return ( [mapping[match["ref"]] for match in matches], [str(match["ref"]) for match in matches], # + f" (score {match['score']})") # good debug )
[docs]def parse_entry_for_subcategories(entry): """ Parse a command docstring for special sub-category blocks: Args: entry (str): A help entry to parse Returns: dict: The dict is a mapping that splits the entry into subcategories. This will always hold a key `None` for the main help entry and zero or more keys holding the subcategories. Each is itself a dict with a key `None` for the main text of that subcategory followed by any sub-sub-categories down to a max-depth of 5. Example: :: ''' Main topic text # SUBTOPICS ## foo A subcategory of the main entry, accessible as `help topic foo` (or using /, like `help topic/foo`) ## bar Another subcategory, accessed as `help topic bar` (or `help topic/bar`) ### moo A subcategory of bar, accessed as `help bar moo` (or `help bar/moo`) #### dum A subcategory of moo, accessed `help bar moo dum` (or `help bar/moo/dum`) ''' This will result in this returned entry structure: :: { None: "Main topic text": "foo": { None: "main topic/foo text" }, "bar": { None: "Main topic/bar text", "moo": { None: "topic/bar/moo text" "dum": { None: "topic/bar/moo/dum text" } } } } """ topic, *subtopics = _RE_HELP_SUBTOPICS_START.split(entry, maxsplit=1) structure = {None: topic.strip("\n")} if subtopics: subtopics = subtopics[0] else: return structure keypath = [] current_nesting = 0 subtopic = None # from evennia import set_trace;set_trace() for part in _RE_HELP_SUBTOPIC_SPLIT.split(subtopics.strip()): subtopic_match = _RE_HELP_SUBTOPIC_PARSE.match(part.strip()) if subtopic_match: # a new sub(-sub..) category starts. mdict = subtopic_match.groupdict() subtopic = mdict["name"].lower().strip() new_nesting = len(mdict["nesting"]) - 1 if new_nesting > MAX_SUBTOPIC_NESTING: raise RuntimeError( f"Can have max {MAX_SUBTOPIC_NESTING} levels of nested help subtopics." ) nestdiff = new_nesting - current_nesting if nestdiff < 0: # jumping back up in nesting for _ in range(abs(nestdiff) + 1): try: keypath.pop() except IndexError: pass elif nestdiff == 0: # don't add a deeper nesting but replace the current try: keypath.pop() except IndexError: pass keypath.append(subtopic) current_nesting = new_nesting else: # an entry belonging to a subtopic - find the nested location dct = structure if not keypath and subtopic is not None: structure[subtopic] = part else: for key in keypath: if key in dct: dct = dct[key] else: dct[key] = {None: part} return structure